THE GENUS COLLYBIA. 



Collybia is a genus fairly well separated from the adjoin- 

 ing genera. From Mycena it is distinguished macroseopically by 

 the generally rather flat cap with slightly incurved edge and 

 microscopically by want of the cystidia characteristic to this 

 latter genus. (In most Collybias the gills either have no cystidia 

 at all or inconspicuous hairshaped ones). — Some neighbouring 

 species of Clitocybe differ in having subdecurrent gills, while in 

 Collybia they are generally adnexed. Still it appears to me not 

 unlikely that it would be preferable to transfer to Collybia some 

 of the Clitocybe dijformes (Fries). Their gills are not truly decur- 

 rent and their stem is tough and elastic almost as the stem of 

 a genuine Collybia. But as any deviation from the old estab- 

 lished nomenclature and classification (if it be not a marked im- 

 provement) should be avoided, I leave them in Clitocybe. 



Also some species of Tricholoma show strong affinity to Col- 

 lybia. This is especially true of T. melaleiicum and its allies. In 

 fact Agaricus stridulus Fr. - - which the author places in Colly- 

 bia — evidently belongs to the melahucum-h'ihe and should not 

 be kept apart trom it. To make as little derangement as pos- 

 sible I therefore shall transfer Ag. stridulus to Tricholoma and 

 place it with its numerous relatives. To Tricholoma I also refer 

 the ambiguous Ag. leucophæatus Karst., which the author at dif- 

 ferent times has placed in Collybia, Tricholoma and Lyophyllum. 

 Within the genus Naucoria the little tribe which might be called 

 »Pisciodoræ« also shows a marked affinity to Collybia. These 

 very intimately related species are now by most authors scattered 

 about, in a very unsatisfactory way, in different genera (Colly- 

 bia, Nolanea, Naucoria). From the genus Nolauea, as now un- 

 derstood, they are excluded by having smooth spores. But the 



